How does the author use ethos in 'The damnation of a canyon'?

getting first hand experince. also using something flashy or a celeb to get you to like it.

the author gives facts about the cost of navigating the canyon before and after the dam was

built

crowded out

the glen canyon dam and the creation of lake powell destroyed the area's natural habitat

the author offers definitions of Words in order to clarify the terms for the reader

by making it known that his opinion is based on firsthand experience

the author gives the reader facts about the area's animal and plant life both before and after the dam was built

the construction of the glen canyon dam destroyed the area's natural habitat